I created a Telegram Group for CodeForces users.
The link to join is https://t.me/CodeForcesGroup
You can also write @CodeForcesGroup on Telegram and click on it to go to the group.
It's a supergroup (so there's up to 5000 members) and it's public.
As this group will be for everyone, please use English in the group as not everyone speaks other languages.
For those who doesn't have Telegram or never joined a group, you can join a group in Telegram without sharing your phone number or username if you don't want to share them (you can configure this in your profile).